Electrical connector with multiple modes of compliance

ABSTRACT

A solderless connector with multiple modes of compliance providing an initial insertion force differing from the secondary insertion force. The connector has multiple compliant members that can be independently adjusted to accommodate a wide range of circuit members. The connector allows the contact members to be arranged with a fine pitch without shorting. The multiple compliant members accommodate a wide range of thermal and vibrational effects, and can be configured to accommodate a wide range of compression distances. An electrically insulative connector housing is positioned substantially between the first and second circuit members. A resilient contact member is positioned generally within the connector housing. The contact member has resilient first and second circuit interface portions. The resilient contact member comprises a first compliant member. At least one end stop is provided for engaging with the contact member in a second mode of compliance. A resilient, dielectric encapsulating material surrounds a portion of the resilient contact member. The encapsulating material comprises a second compliant member, such that the first and second compliant members are capable of providing a first mode of compliance. In an alternate embodiment, resilient material may be located adjacent to a rigid contact member.

The present application is a divisional of U.S. application Ser. No.09/305,165 (allowed) filed May 4, 1999, which is a divisional of U.S.application Ser. No. 08/852,116 filed May 6, 1997 (now U.S. Pat. No.5,938,451) and a continuation-in-part of application Ser. No. 08/955,563(now U.S. Pat. No. 5,913,687) filed Oct. 17, 1997. The presentapplication is also a continuation-in-part of application Ser. No.09/182,164 (Pending) filed Oct. 29, 1998, which is based uponprovisional application serial No. 60/063,927 filed Oct. 31, 1997(Abandoned).

FIELD OF THE INVENTION

The present invention is directed to a solderless connector withmultiple modes of compliance providing an initial insertion forcediffering from the secondary insertion force, and more particularly, toa connector having multiple compliant members that can be independentlyadjusted.

BACKGROUND OF THE INVENTION

The current trend in connector design for those connectors utilized inthe computer field is to provide both high density and high reliabilityconnectors between various circuit devices. High reliability for suchconnections is essential due to potential system failure caused bymisconnections of devices. Further, to assure effective repair, upgrade,testing and/or replacement of various components, such as connectors,cards, chips, boards, and modules, it is highly desirable that suchconnections be separable and reconnectable in the final product.

Pin-type connectors soldered into plated through holes or vias are amongthe most commonly used in the industry today. Pins on the connector bodyare inserted through plated holes or vias on a printed circuit board andsoldered in place using conventional means. Another connector or apackaged semiconductor device is then inserted and retained by theconnector body by mechanical interference or friction. The tin leadalloy solder and associated chemicals used throughout the process ofsoldering these connectors to the printed circuit board have come underincreased scrutiny due to their environmental impact. The plastichousings of these connectors undergo a significant amount of thermalactivity during the soldering process, which stresses the component andthreatens reliability.

The soldered contacts on the connector body are typically the means ofsupporting the device being interfaced by the connector and are subjectto fatigue, stress deformation, solder bridging, and co-planarityerrors, potentially causing premature failure or loss of continuity. Inparticular, as the mating connector or semiconductor device is insertedand removed from the present connector, the elastic limit on thecontacts soldered to the circuit board may be exceeded causing a loss ofcontinuity. These connectors are typically not reliable for more than afew insertions and removals of devices. These devices also have arelatively long electrical length that can degrade system performance,especially for high frequency or low power components. The pitch orseparation between adjacent device leads that can be produced usingthese connectors is also limited due to the risk of shorting.

Another electrical interconnection method is known as wire bonding,which involves the mechanical or thermal compression of a soft metalwire, such as gold, from one circuit to another. Such bonding, however,does not lend itself readily to high density connections because ofpossible wire breakage and accompanying mechanical difficulties in wirehandling.

An alternate electrical interconnection technique involves placement ofsolder balls or the like between respective circuit elements. The solderis reflowed to form the electrical interconnection. While this techniquehas proven successful in providing high density interconnections forvarious structures, this technique does not allow facile separation andsubsequent reconnection of the circuit members.

An elastomer having a plurality of conductive paths has also been usedas an interconnection device. The conductive elements embedded in theelastomeric sheet provide an electrical connection between two opposingterminals brought into contact with the elastomeric sheet. Theelastomeric material that supports the conductive elements compressesduring usage to allow some movement of the conductive elements. Suchelastomeric connectors require a relatively high force per contact toachieve adequate electrical connection, exacerbating non-planaritybetween mating surfaces. Location of the conductive elements isgenerally not controllable. Elastomeric connectors may also exhibit arelatively high electrical resistance through the interconnectionbetween the associated circuit elements. The interconnection with thecircuit elements can be sensitive to dust, debris, oxidation,temperature fluctuations, vibration, and other environmental elementsthat may adversely affect the connection.

It is believed that a high density, repeatable, solderless, electricalconnector that is tolerant to dust, debris, thermal and vibrationaleffect, and relatively easy to manufacture would constitute asignificant advance in the art.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to a solderless connector withmultiple modes of compliance providing an initial insertion forcediffering from the secondary insertion force. The connector has multiplecompliant members that can be independently adjusted to accommodate awide range of circuit members. The present connector allows the contactmembers to be arranged with a fine pitch without shorting. The multiplecompliant members accommodate a wide range of thermal and vibrationaleffects, and can be configured to accommodate a wide range ofcompression distances.

The connectors of the present invention may be used for electricallyconnecting first and second circuit members. Each circuit member hasfirst and second operative surfaces with connector members,respectively.

In a first embodiment, an electrically insulative connector housing ispositioned substantially between the first and second circuit members. Aresilient contact member is positioned generally within the connectorhousing. The contact member has resilient first and second circuitinterface portions. The resilient contact member comprises a firstcompliant member. At least one end stop is provided for engaging withthe contact member in a second mode of compliance. A resilient,dielectric encapsulating material surrounds a portion of the resilientcontact member. The encapsulating material comprises a second compliantmember, such that the first and second compliant members are capable ofproviding a first mode of compliance.

Elastic deformation of the resilient encapsulating material and thecontact member comprises the first mode of compliance. Deformation ofthe contact member during the first mode of compliance is typicallyminimal. Elastic deformation of the contact member in response toengagement with an end stop comprises the second mode of compliance.

At least one support member may be provided for supporting the contactmember. In one embodiment, the support member comprises a pivot pointaround which the contact member rotates. The support member may alsocomprises a flexible filament capable of permitting translational and/orrotational movement of the contact member.

A template having a plurality of slots may be provided for maintaining apreferred spacing between the contact members. The housing preferablyhas an opening extending between first and second surfaces for receivingthe resilient contact. The first and second circuit interface portionsof the resilient contact member extend above or below a first surface ofthe housing.

The second mode of compliance at the first circuit interface portion maybe less than, greater than, or equal to the second mode of compliance atthe second circuit interface portion. The first and second modes ofcompliance are preferably within the elastic limits of the contactmember.

The connector provides an initial insertion force and a secondaryinsertion force with the circuit member. The initial insertion force maybe less than, greater than, or equal to the secondary insertion force.First and second end stops may be provided on the housing for engagingwith the contact member to initiate the second mode of compliance. Thefirst and second circuit interface portions preferably provide a wipingengagement with an opposing connector member.

The resilient contact member may be of a variety of shapes, such ascurvilinear, flat, concave, convex, pointed, or a shape complementary toa shape of the connector member. The resilient contact member may be awire or a piece of a conductive sheet material.

The connector may be configured to maintain the first operative surfaceparallel, perpendicular, or at a fixed angle relative to the secondoperative surface. The circuit members may be selected from the groupconsisting of a card edge, a j-lead device, a land grid array, a pingrid array, a flex circuit, a ribbon connector, a cable, and a ball gridarray.

The resilient contact members are preferably an array of resilientcontact members positioned generally within the connector housing. Thehousing preferably includes an alignment mechanism for aligning thefirst and second circuit interface portions with the connector memberson the first and second circuit members.

In a second embodiment, a rigid contact member is positioned generallywithin the connector housing. The rigid contact member has first andsecond circuit interface portions. A resilient, dielectric encapsulatingmaterial comprising a first compliant member surrounds a portion of thecontact member. The encapsulating material is capable of providing afirst mode of compliance. A first resilient material comprising a secondcompliant member is interposed between the rigid connector member and anend stop on the housing, whereby the first and second compliant membersare capable of providing a second mode of compliance.

The present invention also includes an assembly of the first and secondcircuit members operatively connected by the present connector.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary embodiment of the presentconnector.

FIG. 2A is a side sectional view of the connector of FIG. 1.

FIGS. 2B and 2C are perspective views of alternate contact members foruse in the connector of FIG. 2A.

FIG. 3 is a side sectional view of an assembly of circuit membersincorporating the connector of FIG. 1.

FIG. 4A is a side sectional view of a connector for engagement with asolder ball device.

FIG. 4B is a perspective view of the contact member of FIG. 4A.

FIG. 5A is a side sectional view of an alternate connector forengagement with a solder ball device.

FIG. 5B is a perspective view of the contact member of FIG. 5A.

FIG. 6A is a side sectional view of a connector for engagement with aj-lead device.

FIG. 6B is a perspective view of the contact member of FIG. 6A.

FIG. 7A is a side sectional view of a connector for engagement with anedge card connector.

FIG. 7B is a perspective view of the contact member of FIG. 7A.

FIG. 8A is a side sectional view of a connector for engagement with acircuit board.

FIG. 8B is a perspective view of the contact member of FIG. 8A.

FIG. 9A is a side sectional view of an alternate connector forengagement with a circuit board.

FIG. 9B is a perspective view of the contact member of FIG. 9A.

FIG. 10A is a side sectional view of an alternate connector forengagement with a circuit board.

FIG. 10B is a perspective view of the contact member of FIG. 10A.

FIG. 11A is a side sectional view of a connector for engagement with apin lead device.

FIG. 11B is a perspective view of the contact member of FIG. 11A.

FIG. 12A is a side sectional view of an alternate connector according tothe present invention.

FIG. 12B is a perspective view of the contact member of FIG. 12A.

FIG. 12C is a side sectional view of an alternate connector of FIG. 12A.

FIG. 13 is a perspective view of the connector of FIG. 12A.

FIG. 14A is a side sectional view of a connector according to thepresent invention for use with an edge card device.

FIG. 14B is a perspective view of the contact member of FIG. 14A.

FIG. 15 is a side sectional view of a connector according to the presentinvention for use with a j-lead device.

FIG. 16A is a side sectional view of a connector according to thepresent invention for use with a solder ball device.

FIG. 16B is a side sectional view of an alternate connector according tothe present invention for use with a solder ball device.

FIG. 17 is a side sectional view of a connector according to the presentinvention for use with a pin lead device.

FIG. 18 is a perspective view of an alternate connector according to thepresent invention.

FIG. 19 is a sectional view of the connector of FIG. 18 prior toengagement with a circuit member.

FIG. 20 is a sectional view of the connector of FIG. 18 after engagementwith a circuit member.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a perspective view of an exemplary embodiment of the presentsolderless connector 40. A plurality of resilient contact members 42 areretained in a housing 44 by an encapsulating material 46. The housing 44preferably includes an alignment mechanism, such as openings 82. Thedensity and spacing of the resilient contact members 42 may be alteredto accommodate various circuit members.

FIG. 2A is a side sectional view of the solderless connector 40positioned to engage with a first circuit member 50 and a second circuitmember 52. The first circuit member 50 has a first operative surface 54containing a solder ball device 56. The second circuit member 52 has asecond operative surface 58 containing a connector pad 60. The circuitmembers 50, 52 may be printed circuit boards, circuit modules,integrated circuit devices, cable, flex circuit, ribbon connector,semiconductor devices, including surface mounted devices, and a varietyof other electrical components.

The resilient contact member 42 is retained in the housing 44 by aresilient, dielectric encapsulating material 46. FIGS. 2B and 2C providea perspective views of contact members 42B, 42C, respectively, havingprongs 88 to assist in locating the contact members prior toencapsulation. The contact member 42 may optionally be retained in thehousing 44 by mechanical means, such as suspension filaments 43illustrated in FIG. 2A. The filaments 43 are preferably anchored to thehousing 44. The filaments 43 may be permanent or may be removed afterapplication of the encapsulating material 46. The suspension filaments43 may be a rigid material or a flexible material. They are preferablyflexible, but not extendible, so as to permit limited translational androtational movement of the contact member 42. Translational movementrefers to movement having horizontal and/or vertical components.

The contact member 42 has a first circuit interface portion 62 that mayextend above a first surface 64 of the housing 44. A second circuitinterface portion 66 of the contact member 42 extends above the secondsurface 68 of the housing 44. Either of the circuit interface portions62, 66 may be recessed below the surfaces 64, 68 of the housing 44.Distal end 70 of the contact member 42 is positioned opposite end stop72 on the housing 44. Center portion 75 of contact member 42 ispositioned opposite end stop 78 on the housing 44. Distal end 74 of thecontact member 42 is located opposite end stop 76 on the housing 44.

Alignment of the two circuit members 50, 52 relative to the connector 40may be provided by utilizing a protruding pin 80 which extends from acover 81 extending over the circuit member 50. The pin 80 is aligned andpositioned with corresponding opening 82 in the housing 44. A receivingopening 84 is provided in the circuit member 52 for completing thealignment process. It is understood that other means of alignment arereadily possible, including the provision of pins extending fromopposing surfaces (upper and lower) of the housing 44 for insertionwithin corresponding openings within the respective circuit members 50,52. In actual application, two or more alignment mechanisms, such as theprotruding pin 80, would typically be provided to achieve properalignment of the components 50, 52, 40. Other mechanisms for retainingthe circuit members 50, 52 in a functional engagement with the connector40 are disclosed in U.S. Pat. Nos. 4,445,735 (Bonnefoy); 4,593,961(Cosmo); 4,793,814 (Zifcat et al.); 5,061,192 (Chapin et al.); and5,096,426 (Simpson et al.).

The housing is preferably constructed of a dielectric material, such asplastic. Suitable plastics include phenolics, polyesters, and Ryton®available from Phillips Petroleum Company. The contact member ispreferably constructed of copper or similar metallic materials such asphosphor bronze or beryllium-copper. The contact members are preferablyplated with a corrosion resistant metallic material such as nickel,gold, silver, or palladium. Examples of suitable encapsulating materialsinclude Sylgard® available from Dow Corning Silicone of Midland, Mich.and Master Sil 713 available from Master Bond Silicone of Hackensack,N.J.

FIG. 3 is a side sectional view of the connector 40 incorporated into anassembly comprising circuit members 50, 52. As the connector 40 ispressed onto the circuit interface portion 66, it comes in contact withthe pad 60. The compliant encapsulant 46 allows for initial movement ofthe distal end 74 until it contacts end stop 76 on the housing 44. Themovement of the distal end 74 preferably includes both vertical andhorizontal components so as to cause a wiping action of the circuitinterface portion 66 across the surface of the pad 60.

Elastic deformation of the contact member 42 and movement of the contactmember 42 within the relatively soft encapsulating material 46 defines afirst mode of compliance. The filaments 43 may also contribute to thefirst mode of compliance where present. The first mode of compliancecompensates for non-planarity of the contact members on the circuitmember 52. A relatively soft encapsulating material 46 provides arelatively low initial insertion force for the present connector 40.Insertion force refers to engagement of the present connector 40 withone or more circuit members 50, 52.

After the distal end 74 of the contact member 42 is engaged with the endstop 76, the base metal of the contact acts as a load spring, providingthe second mode of compliance. The end stop 76 prevents compressionbeyond the elastic limit of the contact 42 or the encapsulant 46.Similarly, the distal end 70 of the contact 42 then encounters end stop72 on the housing 44, stopping rotational and translational movement ineither the horizontal or vertical directions.

The first mode of compliance is determined primarily by the resilienceof the encapsulating material 46, although the elastic deformation ofthe contact member 42 and the filaments 43 may also be factors. Theencapsulant 46 provides a relatively large range of motion at a lowforce, allowing for the contact 56 to achieve continuity and planaritydespite a significant mismatch. The filaments 43 can help define therotational or translational movement of the contact member 42 during thefirst mode of compliance.

Once the contact member 42 is compressed against the end stops 72, 78,the base metal substantially defines the second mode of compliance,providing long term connection that resists failure due to fatigue,vibration, temperature fluctuation, and excessive or repeated insertion.The second circuit interface portion 66 operates similarly, although theinitial and secondary insertion forces may vary.

The significance of the present connector 40 is that interconnectionbetween the contact member 42 and the device leads 56, 60 isindependently acting and independently controlled. For example, theconnector 40 is capable of having a different first mode of compliancefor the first and second circuit interface portions 62, 66,respectively, by using two or more encapsulating materials. The geometryor thickness of the contact member may also be adjusted to provide adifferent second modes of compliance at the first and second circuitinterface portions 62, 66. For example, the first circuit interfaceportion 62 provides greater resistance to the contact 56 in the secondmode of compliance. The geometry of the second circuit interface portion66 is such that the resistance provided to the contact 60 in the secondmode of compliance is less than the resistance provided by the firstcircuit interface portion.

The present methodology permits the size, shape, location or material ofthe contact member and the composition, durometer value and quantity ofthe encapsulating material, to be varied to accommodate a wide range ofconnector applications. The present connector 40 may also be configuredto provide a relatively short electrical path. The connector 40 iscapable of achieving a fine pitch that typically cannot be achieved bypin type connectors. The present connector 40 does not rely on theencapsulant as the sole means of support and does not require theconnection members to be deformed in order to gain continuity with thecircuit members 50, 52.

For conventional semiconductor device applications, the encapsulatingmaterial 46 provides a low initial insertion force in the range of about10 grams to about 30 grams. The contact member provides a highersecondary insertion force in the range of about 40 grams to about 100grams. The resulting electrical interconnection provides a higher longterm force load toward the end of its engagement motion to ensure longterm continuity without failure due to fatigue, compression set, oroxidation.

FIG. 4A illustrates an alternate connector 40A suitable for use with asolder ball device. FIG. 4B is a perspective view of the contact member42A. The first circuit interface portion 62A is preferably configuredfor engagement with a ball grid array, such as shown on circuit member50 of FIG. 2. Connector member 42A is retained in housing 44A byencapsulating material 46A. Distal end 70A is retained opposite end stop72A and distal end 74A is retained opposite end stop 76A byencapsulating material 46A. FIGS. 5A and 5B illustrate an alternateconnector 40B suitable for use with a solder ball device. The firstcircuit interface portions 62B of the contact member 42B are configuredfor engagement with a solder ball device at two locations. The twolocations of the first circuit interface portions 62B preferably extendabove the surface of the encapsulant 46B.

FIG. 6A is a side view of an alternate connector 90 according to thepresent invention particularly usefull with a J-lead device 92 on acircuit member 94. Distal end 104 of contact member 96 is retained in aspaced relationship from end stop 106 on the housing 98 by encapsulatingmaterial 100. Similarly, distal end 108 of the contact member 96 isretained in a spaced relationship from the end stop 110 by encapsulatingmaterial 102. The contact member 96 is attached to housing 98 byencapsulating materials 100, 102. The encapsulating materials 100, 102may be the same or different materials. For example, encapsulatingmaterial 100 may have a durometer value of about 25, while the material102 has a durometer value of about 60.

When the J-lead device 92 is brought into engagement with the circuitinterface portion 112 on the contact member 96, the distal ends 104, 108initially move within the encapsulating material 100, 102, respectively,in a first mode of compliance. Again, deformation of the contact member96 may provide a component of the first mode of compliance. Once thedistal ends 104, 108 engage with the end stops 106, 110, respectively,the contact member 96 deforms within its elastic limit in a second modeof compliance. FIG. 6B is a perspective view of the contact member 96 ofFIG. 6A.

FIG. 7A is a side sectional view of the present connector 120 for use asan edge card connector. The housing 122 forms a slot 124 for receivingan edge of a card 126 having at least one connector pad 128. A contactmember 130 is positioned within an encapsulating material 132 so that acircuit interface portion 134 protrudes into the slot 124. Theencapsulating material 132 retains distal end 136 of the contact member130 in a spaced relationship with end stop 138. Similarly, theencapsulating material retains distal end 140 of the contact member 130in a spaced relationship from end stop 142. FIG. 7B provides aperspective view of the contact member 130.

As the card 126 is inserted into the slot 124, the circuit interfaceportion 134 is brought into engagement with the contact 128. Deformationof the encapsulating material 132 and the contact member 130 provide afirst mode of compliance whereby the distal end 136 moves toward the endstop 138. Similarly, as the second circuit interface portion 144 isbrought into engagement with a connector member (not shown), the distalportion 140 moves in a first mode of compliance toward the end stop 142.Once the distal portions 136, 140 are engaged with the end stops 138,142, respectively, the contact member 130 operates as a load spring in asecond mode of compliance and deforms within its elastic range.

FIG. 8A is a side sectional view of a connector 150 according to thepresent invention for electrically connecting with a connector pad 152.A contact member 154 is retained within housing 156 by encapsulatingmaterial 158. The encapsulating material 158 retains distal end 160 ofthe contact member 154 in a spaced relationship from end stop 162. Asthe connector pad 152 is brought into engagement with the circuitinterface portion 164 of the contact member 154, the distal end 160 isdisplaced in a first mode of compliance until it engages with the endstop 162. Deformation of the contact member 154 may provide a componentof the first mode of compliance. A center portion 166 of the contactmember 154 pivots on a portion 168 of the housing 156 so that engagementwith the contact pad 152 causes the contact member 154 to rotate in acounterclockwise direction. Circuit interface portion 170 is similarlydisplaced when brought into engagement with a connector member (notshown). FIG. 8B is a perspective view of the contact member 154 of FIG.8A. Once the distal end 160 engages with the end stop 162, the contactmember 154 operates as a load spring and deforms within its elasticrange.

FIG. 9A is an alternate connector 150A in which the contact member 154Ahas a shape designed to provide greater resistance in the second mode ofcompliance. In particular, the sharp point formed in the contact member154A at the circuit interface portions 164A, 170A provides greaterresistance to elastic deformation than the curved circuit interfaceportions 164, 170 illustrated in FIG. 8A. FIG. 9B is a perspective viewof the contact member 154A of FIG. 9A.

FIG. 10A is a side sectional view of an alternate connector 150Baccording to the present invention. The contact member 154B has a shapeintended to provide less resistance in the second mode of compliancethan provided by the contact member 154 of FIG. 8A. Although thecurvature of the circuit interface portions 164B, 170B correspondsgenerally to that shown in FIG. 8A, the inverted curvature of thecontact member 154B provides for less resistance during the second modeof compliance, and hence a lower secondary insertion force.

FIG. 11A is a side sectional view of a connector 180 according to thepresent invention for engagement with a pin grid array device 182.Housing 184 has a slot 186 for receiving pin 188. Contact member 190 ispositioned adjacent to slot 186. Distal ends 192, 194 of the contactmember 190 are retained in a spaced configuration from end stops 196,198, respectively, of the housing 184. FIG. 11B is a perspective view ofthe contact member 190.

FIG. 12A is a side sectional view of an alternate connector 200according to the present invention. A contact member 202 is located in ahousing 204. A first circuit interface portion 206 on the contact member202 extends above a surface 208 of the housing 204. The second circuitinterface portion 210 extends above a surface 209 of the housing 204.Alternately, the first and second interface portions 206, 210 may berecessed below the surfaces 208, 209, respectively. Resilient materials212, 213 are interposed between the rigid connector member 202 and thehousing 204 in two separate locations. The connector member 202 andresilient members 212, 213 are retained within the housing 204 by anencapsulating material 214.

The contact member 202 may be supported by one or more suspensionfilament 220, 227A, 227B to precisely locate the contact member 202during encapsulation. The suspension filaments 220, 227A, 227B arepreferably anchored to the housing 204 (see FIG. 13). The suspensionfilaments 220, 227A, 227B may be permanent or may be removed afterapplication of the encapsulating material 214.

The suspension filaments 220, 227A, 227B may be a rigid material or aflexible material. The suspension filaments 220, 227A-227B arepreferably flexible, but not extendible so as to permit limitedtranslational and rotational movement of the contact member 202. Theconductive elements 202 may be positioned along the filament 220 in sucha way that a minimum of two moment arms are created as a result of thelocation of the interface point along the body of the contact member202. A single rigid suspension member 220 may be located at a singlepoint 221 near or along the major axis of the contact member 202 suchthat it provides a pivot point for rotation. Alternatively, secondand/or third suspension filaments 227A, 227B may optionally be included(see FIGS. 19 and 20).

The filaments 220, 227A, 227B may be located at any point along the bodyof the contact member 202 such that it will be positioned in a desiredlocation when the connector 200 is at rest, but will not be restrictedfrom a desired amount of transitional or rotational movement. Thesuspension filaments 220, 227A, 227B may remain in place afterencapsulation, and will result in a reinforced composite that willfunction in practice in a manner different from that of the encapsulantalone. The filaments 220, 227 will allow the desired motion of thecontact member 202 upon incident with the opposing terminals that are tobe connected, but will restrict movement in one or more directions aswell as limit the total travel of the contact member 202, resulting inan action that will prevent damage to the encapsulant 214, the secondaryresilient members 212, 213, the contact member 202, or the opposingterminal 216. The nature of contact member 202 action will allow foreach member to move independent of its neighbor through a rangesufficient to accommodate coplanarity variances between the conductiveelements and any of the opposing terminals to be connected.

The contact member 202 is preferably rigid. As the connector member 216on the first circuit member 218 is brought in contact with the firstcircuit interface portion 206, the encapsulating material 214 allows forboth translational and rotational movement of the contact member 202around a filament 220. Movement of the contact member 202 within theencapsulating material 214 comprises a first mode of compliance,resulting in a relatively low initial insertion force with a circuitmembers, such as 218. The compliant encapsulant 214 allows verticalmovement until contact member 202 encounters one or both of theresilient materials 212, 213. The resilient materials 212, 213 incombination with the encapsulant 214 (and optionally the filaments 220,227A, 227B) provide the second mode of compliance. In the preferredembodiment, the resilient materials 212, 213 are stiffer (higherdurometer value) than the encapsulant 214, so that the secondaryinsertion force is larger than the initial insertion force. The contactmember 202 eventually contacts end stops 222, 223 on the housing 204.Alternatively, the resilient materials 212, 213 may be selected so thatthe secondary insertion force is less than the initial insertion force.

The encapsulant 214 provides a relatively large range of motion at a lowforce, allowing for the contact 202 to achieve continuity and planaritydespite a significant mismatch. In one embodiment, the filament 220 isnot a rigid support, allowing for both rotational and translationalmovement of the contact 202. Once the contact member 202 is compressedagainst the resilient material 212, 213, the second mode of complianceprovides long term connection that resists failure due to fatigue,vibration, temperature fluctuation, and excessive or repeated insertion.In an alternate embodiment in which the contact member 202 is flexible,the connector 200 will operate as a loading spring, as discussed abovein connection with FIGS. 1-3.

FIG. 12B is a perspective view of a contact member 202 having anopenings 221, 227 for receiving the filament 220. FIG. 12C illustratesan alternate connector 200A in which the opening 221A of the contactmember 202A is a slot structure for receiving the filament 220A.

FIG. 13 is a perspective view of the connector 200 having a plurality ofcontact members 202 separated by spacers 224. The spacers may beincorporated into the filament 220. Alternatively, the contact members202 may be retained in the desired spaced relationship duringapplication of the encapsulating material 214 (see FIG. 12A). Thefilament 220 is supported by the housing 204. The spacing between thecontact members 202 may be adjusted by altering the thickness of thespacers 224. The present connector is preferably capable of providingcontact members having a pitch of less than about 0.4 mm, and morepreferably less than about 0.2 mm. The spacers 224 may be constructedfrom a variety of dielectric materials, such as plastic or ceramics.

FIG. 14A is a side sectional view of an alternate connector 230 in whicha cam-shaped contact member 232 is at least partially retained in ahousing 234 by a filament 244. FIG. 14B is a perspective view of thecontact member 232. A resilient material 238 is located adjacent to thecontact member 232 on the side opposite encapsulating material 236. Thehousing 234 is configured for receiving a card edge device 240 havingcontact members 242 on at least one surface. As discussed in connectionwith FIG. 12A, the contact member 232 displaces the encapsulatingmaterial 236 in a first mode of compliance. Subsequently, the contactmember 232 engages the resilient material 238 to initiate a second modeof compliance. The housing 234 is configured to limit the maximumrotation of the contact member 232 about the filament 244.

FIG. 15 is a side sectional view of an alternate connector 250configured for engagement with a J-lead device 252 on a circuit member254. The contact member 256 is positioned on a filament 258 adjacent toencapsulating material 260 and resilient material 262. The resilientmaterial preferably has a higher durometer value than the encapsulatingmaterial 260.

FIG. 16A illustrates an alternate connector 270A for engagement with asolder ball device 272 on a circuit member 274. Connector element 276Arotates around pivot point 278A within connector housing 280A. The firstcircuit interface portion 282A of the contact member 276A includes adepression 284A to facilitate engagement with the ball member 272 of thecircuit member 274. A second circuit interface portion 286A protrudesfrom the bottom of the housing 280A for engagement with a second circuitmember (not shown). FIG. 16B is an alternate connector 270B in which thecontact member 276B is in a generally vertical configuration forrotation around the pivot point 278B.

FIG. 17 is a side sectional view of an alternate connector 290 accordingto the present invention configured for engagement with a pin grid arraydevice 292 having a pin 294. The contact member 296 rotates about pivotpoint 298 within the housing 300. Encapsulating material 302 provides afirst mode of compliance and resilient material 304 provides a secondmode of compliance.

FIG. 18 is a perspective view of a connector assembly 320 having anarray of contact members 322. A template 324 with a plurality of slots326 maintains the preferred spacing between the contact members 322. Theconnector assembly may be a wide variety of sizes and shapes.

FIG. 19 is a side sectional view of a pair of contact members 322 ofFIG. 18, retained in the connector housing 328 by a pair of flexiblefilaments 330, 331 and an encapsulating material 332. A resilientmaterial 334 is located adjacent to the contact member 322 in twolocations. FIG. 20 illustrates the motion of the contact members 322 andfilaments 330, 331 after engagement with a circuit member (not shown).The contact members 322 compress the resilient material 334. In additionto the rotational movement of the contact members 322, the translationalmovement of the contact members 322 is illustrated by the movement ofthe filaments 330 generally in a direction “A” toward the center of theconnector 330. The filaments 331 move generally in a direction “B” awayfrom the center of the connector 330.

Patents and patent applications disclosed herein, including those citedin the background of the invention, are hereby incorporated byreference. Other embodiments of the invention are possible. It is to beunderstood that the above description is intended to be illustrative,and not restrictive. Many other embodiments will be apparent to those ofskill in the art upon reviewing the above description. The scope of theinvention should, therefore, be determined with reference to theappended claims, along with the full scope of equivalents to which suchclaims are entitled.

What is claimed is:
 1. An apparatus comprising: a first circuit memberhaving a first operative surface including connector members; a secondcircuit member having a second operative surface including connectormembers; a connector comprising; an electrically insulative connectorhousing positioned substantially between the first and second circuitmembers; at least one resilient contact member positioned generallywithin the connector housing having resilient first and second circuitinterface portions, the resilient contact member comprise a firstcompliant member; a resilient, dielectric encapsulating materialsurrounding a portion of the resilient contact member comprising asecond compliant member, whereby the first and second compliant membersare capable of providing a first mode of compliance when the contactmember is displaced by one of the circuit members; and at least one endstop against which a portion of the second complaint member is at leastpartially compressed to provide a flexural point where the contactmember elastically deforms in a second mode of compliance.
 2. Theapparatus of claim 1 further comprising an alignment mechanism adaptedto align the first and second electrical circuit members and theconnector.
 3. The apparatus of claim 1 wherein the housing furthercomprises an alignment mechanism adapted to align the first and secondcircuit members with the contact members.
 4. The apparatus of claim 1wherein elastic deformation of the resilient encapsulating materialcomprises at least a portion of the first mode of compliance.
 5. Theapparatus of claim 1 wherein engagement of the contact member with thefirst circuit member initiates translational movement of the contactmember.
 6. The apparatus of claim 1 further comprising at least onesupport member supporting the contact member.
 7. The apparatus of claim1 comprising a support member that comprises a pivot point around whichat least a portion of the contact member rotates.
 8. The apparatus ofclaim 7 wherein the support member comprises a flexible filament capableof permitting translational movement of the contact member.
 9. Theapparatus of claim 1 wherein the at least one contact member comprises aplurality of contact members.
 10. The apparatus of claim 1 furthercomprising a template having a plurality of slots for maintainingspacing between a plurality of contact members.
 11. The apparatus ofclaim 1 comprising an opening in the housing extending between first andsecond surfaces on the housing adapted to receive the resilient contactmember.
 12. The apparatus of claim 1 wherein the first circuit interfaceportion of the resilient contact member extends above a first surface ofthe housing.
 13. The apparatus of claim 1 wherein translational movementof the first circuit interface portion is less than translationalmovement of the second circuit interface portion.
 14. The apparatus ofclaim 1 wherein the first and second modes of compliance are within theelastic limits of the encapsulating material.
 15. The apparatus of claim1 comprising first and second end stops on the housing for limitingtranslational movement during the second mode of compliance.
 16. Theapparatus of claim 1 wherein the resilient contact member comprises acurvilinear shape.
 17. The apparatus of claim 1 wherein the firstcircuit interface portion comprises a shape complementary to a shape ofthe first circuit connector member.
 18. The apparatus of claim 1 whereinthe resilient contact member comprises a piece of a conductive sheetmaterial.
 19. The apparatus of claim 1 wherein the first and secondcircuit interface portions provides a wiping engagement with an opposingconnector member.
 20. The apparatus of claim 1 wherein the connectorcomprises a configuration capable of maintaining the first operativesurface parallel to the second operative surface.
 21. The apparatus ofclaim 1 wherein the first and second circuit members comprise one ofprinted circuit boards, integrated circuit devices, circuit modules,cables, flex circuits, ribbon connectors, semiconductor devices, orsurface mounted devices.
 22. The apparatus of claim 1 wherein the firstcircuit interface portion is capable of engaging with a connector memberselected from the group consisting of a card edge, a j-lead device, aland grid array, a pin grid array, a flex circuit, a ribbon connector, acable, and a ball grid array.
 23. The apparatus of claim 1 wherein theresilient contact member comprises an array of resilient contact memberspositioned generally within the connector housing.
 24. The apparatus ofclaim 1 wherein the first circuit interface portion comprises acup-shape configured to engage with the connector member of a circuitmember.
 25. The apparatus of claim 1 wherein at least a portion of thesecond mode of compliance is determined by a shape of the contactmember.
 26. The apparatus of claim 1 wherein at least a portion of thesecond mode of compliance is determined by a thickness of the contactmember.
 27. The apparatus of claim 1 wherein the end stops comprises atleast one flat surface on the housing.
 28. The apparatus of claim 1wherein engagement of the contact member at the flexural point initiatesthe second mode of compliance.
 29. The apparatus of claim 1 whereintranslational movement of the first circuit interface portion is greaterthan translational movement of the second circuit interface portion.